Help estimating power draw for server and budgeting for rackspace

Hardware Hub
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Hi - first time poster / long time lurker.

I am planning on getting some rack space to run a small k8s cluster and am trying to estimate my power draw. Plan is to get the following server specs:

  • Epyc 7702 (64c - 200 default tdp)
  • 1 TB ram (16*64gb lrdimm 2400 Mhz - Can’t find data on the power)
  • 12 3.84 TB pm9a3 (Read: <= 11 W Write: <= 13.5 W)

Cursory estimates with GPT and the like have put me at the following

200W (cpu) + 16 * 5W (ram) + 12 * 12W = 424W

This seems high so I wanted to get some feedback here.

I am planning on getting 10u of rack space which comes with 5A @ 208 A+B so based on my estimation - it seems like I can only fit 2 servers per circuit which feels a little low considering that would only fill up 40% of the rackspace. Ideally I would be able to get 6 nodes in there plus a switch. I’ll be running k8s so I want to run 3 nodes on each circuit with masters running in VMs such that if I did lose a circuit I would potentially still be able to keep serving traffic.

Any feedback on if my estimates are ok and if it is possible to get 3 nodes on each circuit would be HIGHLY appreciated.

I have run some old beatup servers at home before and currently manage several k8s clusters in the cloud but this is my first rodeo in a real DC as part of an effort to get off the cloud and get the resources my application needs which is very IOPs intensive.

Thank you for your time.

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If I remember, roundabout 6W per stick.

450W sounds about right to me, another 50W may be lost along the way on the mainboard and with a 80Plus Gold PSU, I would guess 550W-ish from the wall.

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Thank you for reply. So given that estimate, I’ll only be able to get 4 servers into that 10u space. Is that common? Considering no GPUs and the CPU not being that high compared to higher end epycs or intel for that matter, just seems odd to only be able to fill half the cabinet.

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So I ended up getting RS500A-E11-RS12U with a couple different processors, mostly 32 core, one 24, and one 64 epycs. With the epyc 7532 (200w tdp) and 500gb of LR ram (8*64), and 12 pm9a3 3.84 tb drives running a fio test with all cores pinned I am seeing 400 watts, idle about 150w.

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